The long range aim of this project is to predict vocal fold movement and sound generation in the larynx from neural inputs. Central to the research project is the design and implementation of a complete quantitative neuromuscular model of the larynx and to adapt this model to existing data or to data to be experimentally obtained as part of the project. The planned work consists in: establishing the dynamic contractile properties and constitutive equations for all laryngeal muscles; to develop a new 3D finite element model that allows simulation of laryngeal posturing; investigating to which degree the compartments of the thyroarytenoid muscle effect adduction, pitch and vocal register in phonation; to determine the role of laryngeal reflexes in vocal fold posturing and in neurologic instabilities of voicing; and finally to develop a set of test utterances that will test the motor capabilities of the larynx and vocal disorders of laryngeal control.